The mathematical formalism of compartmental models as applied to physiological kinetics is changed in such a way that explicit control mechanisms may be introduced into the models. The control mechanisms are shown by designating specific inter compartmental material flows as controlled flows. These are then described and used in the same way as controlled current sources in electrical networks theory systems containing such controlled flows display improved regulation of specific compartments. Criteria for stability, non-negativity, controllability, observability, and identifiability are being formed for these controlled systems. Specific cases are being sought where changes in this control structure can be related to actual diseased states.